This application claims priority of Taiwan patent application no. 090215444, filed on Sep. 7, 2001.
1. Field of the Invention
The invention relates to a vehicle remote-control system, more particularly to one that incorporates a disarming device for disarming an anti-theft unit of the remote-control system.
2. Description of the Related Art
Referring to FIG. 1, a conventional anti-theft unit for a vehicle is shown to include a signal transmitting key 11 and a vehicle control module 12. Each of the signal transmitting key 11 and the vehicle control module 12 is provided with an antenna 111, 121 such that a disarm signal transmitted wirelessly by the key 11 can be received by the vehicle control module 12. The vehicle control module 12 is coupled to an ignition system 13 of a vehicle so as control activation of the latter. In actual practice, the vehicle control module 12 is able to receive the disarm signal from the key 11 only when the latter is in close proximity, such as within a transmission distance of 2 to 5 cm, with the antenna 121 of the vehicle control module 12. Upon receipt of the disarm signal, the vehicle control module 12 will perform a verification operation. If the disarm signal is found to be valid, the vehicle control module 12 will enable activation of the ignition system 13. Otherwise, the vehicle control module 12 will maintain an inactive state of the ignition system 13. Many methods are available for deactivating the ignition system 13 through the control of the vehicle control module 12. For example, the vehicle control module 12 can control the supply of electric power to the ignition system 13, thereby controlling activation and deactivation of the latter. Hence, the use of the key 11 to control activation of the ignition system 13 can deter theft.
Because the key 11 must be disposed in close proximity with the antenna 121 of the vehicle control module 12 so as to enable activation of the ignition system 13, and because of the subsequent operations that are needed to initiate starting operation of the ignition system 13, the antenna 121 is designed to be in the form of an annular antenna that is mounted around a keyhole in the vehicle. As such, when the key 11 is inserted into the keyhole, the distance between the key 11 and the antenna 121 of the vehicle control module 12 will be about 2 to 3 cm, which is within the required transmission distance, and the disarm signal transmitted by the key 11 can be received by the vehicle control module 12 via the antennas 111, 121. Upon finding the disarm signal to be valid, the vehicle control module 12 will be enabled to activate the ignition system 13. At this time, the key 11 can be turned to initiate starting operation of the ignition system 13 for moving the vehicle.
Presently, vehicles include a starting unit that can be operated via remote control for opening doors, the trunk or hood, for controlling starting operation of the ignition system, etc. However, when both the aforesaid anti-theft unit and the remote-controlled starting unit are incorporated into a vehicle, in order to start the engine of the vehicle by remote control, the key 11 must be disposed in a disarming position, e.g. in the keyhole, so that the vehicle control module 12 can be enabled to activate the ignition system 13. Only then can the starting unit be used to control the ignition system. In other words, it is not possible to start the engine of the vehicle by remote control when the key 11 is not disposed in the disarming position for disarming the vehicle control module 12.
Therefore, the main object of the present invention is to provide a vehicle remote-control system that incorporates a disarming device for disarming an anti-theft unit even when a signal transmitting key of the latter is not disposed in a disarming position.
According to the present invention, a vehicle remote-control system is adapted to control an ignition system of a vehicle, and comprises an anti-theft unit, a starting unit, and a disarming device.
The anti-theft unit includes a signal transmitting key capable of wirelessly transmitting a disarm signal, and a vehicle control module adapted to be coupled to the ignition system, and capable of wirelessly receiving the disarm signal directly from the key when the key is within a first transmission distance from the vehicle control module. The vehicle control module is capable of changing from an armed state, wherein the vehicle control module is adapted to maintain an inactive state of the ignition system, to a disarmed state, wherein the vehicle control module is adapted to activate the ignition system, upon receipt of the disarm signal.
The starting unit including a remote controller operable so as to wirelessly transmit a starting control signal, and a starting device adapted to be coupled to the ignition system and capable of receiving the starting control signal from the remote controller. The starting device generates an enable signal upon receipt of the starting control signal, and is adapted to control starting operation of the ignition system when the vehicle control module is at the disarmed state and the starting device receives the starting control signal.
The disarming device includes a signal connector connected electrically to the starting device so as to receive the enable signal therefrom. The signal connector is enabled by the enable signal so as to be capable of wirelessly receiving the disarm signal from the key and so as to be capable of wirelessly transmitting the disarm signal received thereby to the vehicle control module when the key is within a second transmission distance larger than the first transmission distance from the signal connector. The signal connector is inhibited from relaying the disarm signal from the key to the vehicle control module when the signal connector fails to receive the enable signal from the starting device.